Apple Watch Series 12 and Ultra 4 Are On Sale Today: Price and Specs

Apple Watch Series 12 and Apple Watch Ultra 4 are both officially on sale today, September 18, 2026, alongside the iPhone 18 Pro and AirPods 5 — and the headline change across both watches is a new S11 chip paired with what Apple calls a “Health Sensing System” rather than a single flashy new sensor. I’ve worn every Ultra since the original, and this is the first generation where the everyday Series watch and the rugged Ultra genuinely feel like they’re running the same underlying health platform instead of two separate product lines that happen to share a name.

Price and Availability

Apple Watch Series 12 starts at $399 for the 42mm aluminum model, with the larger 46mm case now starting at $449 — a $20 bump over last year’s 46mm pricing that Apple didn’t call out on stage but that’s already showing up in retailer listings. Apple Watch Ultra 4 starts at $799 in Natural Titanium with the Ocean Band. Both are available today directly from Apple, at carriers, and through major retailers in the same 65-plus countries and regions getting the iPhone 18 Pro. If you’d rather spread the cost out, the Series 12 is also available through Apple’s new Apple Upgrade lease program starting around $11.99/month.

What’s Actually New

Both watches share the new S11 chip and an overhauled Health Sensing System, which Apple is positioning as a platform-level upgrade rather than a single feature. Battery life is where the two models genuinely diverge from each other: Series 12 gets up to 24 hours of everyday battery life, with a 15-minute fast charge adding roughly 12 more hours — useful if you forgot to charge it overnight and need enough juice to get through a workday. Ultra 4 is built for a different use case entirely, rated for up to 50 hours of everyday battery life and up to 45 hours specifically during outdoor workout tracking, which matters if you’re the kind of person who takes a GPS watch on an actual multi-day trip rather than a gym session.

Materials and color options expanded meaningfully for Series 12 this year. It’s available in aluminum, titanium, and ceramic cases, with aluminum colors including dark bronze, black, light gold, and space gray; titanium in radiant gold and natural titanium; and ceramic in pearl white and night blue. That’s a wider material spread than Apple has offered on the standard Series watch in a while — ceramic in particular used to be reserved for special editions.

Quick-Reference: Series 12 vs. Ultra 4

Software: watchOS 27 and the New Siri

Every unit shipping today runs watchOS 27 out of the box, built around the same rebuilt Siri that’s launching across Apple’s whole fall lineup. On the Watch specifically, that means more of the Health Sensing System’s output — readiness scores, recovery trends, workout summaries — gets surfaced through conversational Siri queries rather than requiring you to dig through the Fitness app on your phone. It’s a smaller headline feature than the hardware changes, but it’s the piece that’s most likely to actually change how you use the watch day to day.

How This Fits Into Apple’s Bigger Launch Day

The Watch lineup isn’t launching in isolation today. The iPhone 18 Pro and Pro Max go on sale the same day, both running iOS 27 with the same Apple Intelligence and Siri foundation the Watch is built on, and AirPods 5 are shipping alongside both at $129. I’d treat all three as one connected launch rather than separate events — Apple clearly designed this generation’s software story (readiness, health, and Siri) to work across all three devices at once, and buying just one of them means you’re only getting part of that picture. If you’re weighing whether the Ultra 4 is worth the jump from a Series watch, my honest read: buy the Ultra only if you actually use the outdoor workout tracking or multi-day battery regularly. If your workouts fit inside a 24-hour battery cycle, the $400 you save on Series 12 is better spent elsewhere.

One thing to flag if you’re specifically eyeing the Ultra for its rugged case: Apple didn’t announce a new case size or shape this year, so if you already own an Ultra 2 or Ultra 3 band collection, everything should carry over.

Trade-in is also live today if you’re upgrading from an older Watch. Apple’s own trade-in program takes most Series watches from the last several generations, though realistically the credit on anything older than a Series 8 or original Ultra tends to be modest — often more useful as a discount nudge than a meaningful chunk of the purchase price. Several carriers are running their own competing trade-in promotions this week too, so it’s worth a five-minute comparison before you commit rather than assuming Apple’s number is automatically the best one.

Frequently Asked Questions

Is the Apple Watch Series 12 waterproof?

Apple’s Watch lineup has carried water-resistance ratings suitable for swimming for several generations, and Apple hasn’t indicated any change to that for Series 12 or Ultra 4 this year — both remain suitable for swim tracking, with the Ultra 4 rated for more demanding water sports given its case design.

Do I need an iPhone 18 to use the new Apple Watch features?

No. Apple Watch Series 12 and Ultra 4 pair with any iPhone that supports watchOS 27, not specifically the iPhone 18 lineup. You’ll get the same Health Sensing System and Siri features regardless of which current iPhone you’re using.

Why did the 46mm Apple Watch Series 12 get more expensive this year?

Apple raised the 46mm Series 12 price by $20 over the previous generation without publicly explaining the increase during the keynote. The 42mm price held steady at $399, so the increase is specific to the larger case size.

What’s the actual difference in battery life between Series 12 and Ultra 4?

Series 12 is rated for up to 24 hours of everyday use with fast-charge support. Ultra 4 more than doubles that at up to 50 hours everyday and up to 45 hours during active outdoor workout tracking, reflecting its design for longer trips away from a charger.